La Nina’s effects may finally take hold in NC

It’s no secret that I’m not a fan of cold weather. Short, gray days alter my mood for the worse. Bitter cold makes my joints ache. Snow and ice cause transportation issues. I can’t help it. I’m a summer lover, which is why I live in the south. So, back in October, when the Climate Prediction Center issued a statement that La Nina was settling in for the winter, I did a quiet little happy dance.

La Nina tends to bring warmer and drier-than-average weather to the Southeast.

As you can imagine, the first half of December has been disappointing for me. I mean really! Near record-breaking cold, our first wintry mix of the season, and deceptively sunny, brisk days have had me crying foul. Some good La Nina is doing, right?

The reality is that La Nina is not the only factor in our weather. Our recent cold snap has been the product of a more active, wavy pattern over North America – one that brings arctic air from the northwest to the southeast. Its persistence has been good news to my friends who require chilly temperatures to get into the holiday spirit. I think they’ve enjoyed it quite a bit based on the photos of snow all over my Facebook feed last weekend.

Next week, the pattern will change and bring a more horizontal flow across the country. Our storms will be coming from the southern part of the United States, and our temperatures will warm to above normal levels. The cold air will stay to our north, where Snow Miser says it should be. (If you don’t get the reference, please watch “The Year Without a Santa Claus,” or look him up on Youtube.)

cpc map

The Climate Prediction Center’s temperature probability map for December 19-23, shows above-average chances for above-normal.

The Climate Prediction Center forecasted November, December, and January to have better-than-average chances at being warmer than normal back in October, when they noted La Nina’s cooler waters taking hold in the equatorial Pacific Ocean. North Carolina has not really seen that forecast verify so far, but the Global Forecasting System (GFS) long-range model shows a warm-up starting early next week. It’s possible that La Nina’s moderating effects on the South’s weather may finally be coming into play.

Does that mean a white Christmas is highly unlikely for the Triangle? Maybe. Maybe not. It may be a wet Christmas or sleet-filled Christmas if the latest run of the GFS verifies. While rain or sleet will make gift delivery a soggy – or even treacherous – ordeal, our area could use the precipitation. As of today, the U.S. Drought Monitor shows much of North Carolina under abnormally dry conditions with the central portion of the state experiencing moderate drought.

Don’t be too upset or excited about the Christmas forecast. If you’ve read my previous blog posts, you know any model predictions longer than five days away are not as trustworthy as we’d like them to be. I expect the forecast to change several times between now and December 24.

drought map

U.S. Drought Monitor map issued December 14, 2017